AD7861APZ

Overview

The AD7861APZ is an 11-bit resolution, simultaneous sampling analog-to-digital converter (ADC) designed for motor control and three-phase power measurement applications. It features four input channels sampled simultaneously to preserve relative phase information, with VIN1, VIN2, and VIN3 dedicated to stator current acquisition. The device includes four multiplexed auxiliary inputs suitable for slower signals like temperature or bus voltage. Operating on a single +5 V supply, it integrates a 2.5 V reference and supports a system clock range of 6.25 MHz to 12.5 MHz. Conversion requires 40 clock cycles per channel, with a sample-and-hold acquisition time of 1.6 µs at the maximum clock frequency.

Feature Summary

• Simultaneous sampling of four input channels using a dedicated sample-and-hold amplifier array to maintain phase integrity.
• Flexible channel sequencing allowing user-defined acquisition of two, three, or four channels per conversion group.
• Integrated internal 2.5 V reference with external drive capability for system stability.
• Register-based parallel output interface compatible with standard DSP and microcontroller architectures.

Applications

• Motor Control Systems
• Three-Phase Power Measurement
• Data Acquisition

Procurement Notes

Verify the specific suffix APZ corresponds to the –40°C to +85°C industrial temperature range and P-44A package option as listed in the official ordering guide. Confirm RoHS compliance status through the manufacturer's current documentation before finalizing procurement specifications.

Selection Notes

Select this component when simultaneous multi-channel sampling is required to capture phase relationships accurately. Ensure the application operates within the specified 6.25 MHz to 12.5 MHz clock range and utilizes a single +5 V supply. Verify that the 11-bit resolution and 0–5 V input range meet the signal requirements.

Part Context

The AD7861 series is part of Analog Devices' portfolio of multichannel data converters optimized for industrial and automotive environments. It is frequently paired with 16-bit fixed-point digital signal processors to create cost-effective solutions for complex control algorithms requiring precise analog signal digitization.

Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation. Evaluate other Analog Devices SAR ADCs with similar channel counts and sampling rates if direct replacement is necessary.

FAQ

How many channels can be sampled simultaneously?

The AD7861 features a four-channel sample-and-hold amplifier that allows up to four channels to be sampled simultaneously.

What is the operating clock frequency range?

The device supports an external system clock frequency ranging from 6.25 MHz to 12.5 MHz.

How is the auxiliary channel selected?

The auxiliary channel is selected using the S0 and S1 pins, which multiplex one of four auxiliary inputs (AUX0–AUX3) into the ADC channel.